BackgroundGiven the success of cash programs in improving health outcomes and addressing upstream drivers of HIV risk such as poverty and education, there has been an increasing interest in their potential to improve HIV prevention and care outcomes. Recent reviews have documented the impacts of structural interventions on HIV prevention, but evidence about the effects of cash transfer programs on HIV prevention has not been systematically reviewed for several years. Methods and findingsWe did a systematic review of published and unpublished literature to update and summarize the evidence around cash programs for HIV prevention from January 2000 to December 17, 2020. We included studies with either a cash transfer intervention, savings program, or program to reduce school costs. Included studies measured the program's impact on HIV infection, other sexually transmitted infections (STIs), or sexual behaviors. We screened 1,565 studies and examined 78 in full-text review to identify a total of 45 peer-reviewed publications and reports from 27 different interventions or populations. We did not do a meta-analysis given the range of outcomes and types of cash transfer interventions assessed. Most studies were conducted in sub-Saharan Africa (N = 23; South Africa, Tanzania, Malawi, Lesotho, Kenya, Uganda, Zimbabwe, Zambia, and eSwatini) followed by Mexico (N = 2), the United States (N = 1), and Mongolia (N = 1)). Of the 27 studies, 20 (72%) were randomized trials, 5 (20%) were observational studies, 1 (4%) was a case-control study, and 1 (4%) was quasi-experimental. Most studies did not identify a strong association between the program and sexual behaviors, except sexual debut (10/18 finding an association; 56%). Eight of the 27 studies included HIV biomarkers, but only 3 found a large reduction in HIV incidence or prevalence, and the rest found no statistically significant association. Of the studies that identified a statistically significant association with other STIs (N = 4/8), 2 involved incentives for staying free of the STI, and the other 2 were cash transfer programs for adolescent girls that had conditionalities related to secondary schooling. Study limitations include the small number of studies in key populations and examining interventions to reduce school costs and matched saving programs. ConclusionsThe evidence base for large-scale impacts of cash transfers reducing HIV risk is limited; however, government social protection cash transfer programs and programs that incentivize school attendance among adolescent girls and young women show the greatest promise for HIV prevention. Author summary Why was this study done? Cash transfers have become a widely used policy strategy to achieve social protection and development goals in a number of different domains.Recent reviews have documented the impacts of cash transfer interventions on HIV prevention outcomes, but many studies have been done recently and have not yet been captured in these reviews. What did the researchers do and find? To update the current evidence related to cash transfers for HIV prevention, we did a systematic review of quantitative studies of cash transfer interventions, interventions to reduce school costs, and matched savings programs extending from January 2000 to December 2020.Impacts on HIV infection were mixed. Only 3 of the 8 studies that included HIV biomarkers found a reduction in HIV incidence or prevalence.Four of 8 studies that included other sexually transmitted infections (STIs) found a statistically significant association, and all 4 of these studies included conditionalities based on testing STI negative or secondary schooling.A total of 10/18 (56%) interventions identified a statistically significant reduction on delaying sexual debut, in most cases only for girls and not for boys. What do these findings mean? Overall, we find that most evidence to date is limited in demonstrating that cash transfers can reduce HIV infection or have broad reaching impacts on risky sexual behaviors.Social protection cash transfer programs provided to poor or vulnerable households and cash transfers conditional on school attendance were more likely to lead to delays in sexual activity among adolescents generally and reductions in risky sex among adolescent girls, at least while the programs were ongoing.Further research is needed to understand the impact of cash transfer among key populations and when combined with other HIV prevention interventions.
